ASoC: SOF: Convert the generic IPC message injector into SOF client

Move the IPC message injection code out from the debug file as separate
SOF client driver.

Based on the kernel configuration, the device registration for the new IPC
message injector is going to happen in the core.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Link: https://lore.kernel.org/r/20220210150525.30756-9-peter.ujfalusi@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 192 insertions, 0 deletions

diff --git a/sound/soc/sof/sof-client-ipc-msg-injector.c b/sound/soc/sof/sof-client-ipc-msg-injector.c
new file mode 100644
index 000000000000..bce103da4c49
--- /dev/null
+++ b/sound/soc/sof/sof-client-ipc-msg-injector.c
@@ -0,0 +1,192 @@
+// SPDX-License-Identifier: GPL-2.0-only
+//
+// Copyright(c) 2022 Intel Corporation. All rights reserved.
+//
+// Author: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
+//
+
+#include <linux/auxiliary_bus.h>
+#include <linux/completion.h>
+#include <linux/debugfs.h>
+#include <linux/ktime.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/pm_runtime.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <sound/sof/header.h>
+
+#include "sof-client.h"
+
+#define SOF_IPC_CLIENT_SUSPEND_DELAY_MS	3000
+
+struct sof_msg_inject_priv {
+	struct dentry *dfs_file;
+
+	void *tx_buffer;
+	void *rx_buffer;
+};
+
+static int sof_msg_inject_dfs_open(struct inode *inode, struct file *file)
+{
+	struct sof_client_dev *cdev = inode->i_private;
+	int ret;
+
+	if (sof_client_get_fw_state(cdev) == SOF_FW_CRASHED)
+		return -ENODEV;
+
+	ret = debugfs_file_get(file->f_path.dentry);
+	if (unlikely(ret))
+		return ret;
+
+	ret = simple_open(inode, file);
+	if (ret)
+		debugfs_file_put(file->f_path.dentry);
+
+	return ret;
+}
+
+static ssize_t sof_msg_inject_dfs_read(struct file *file, char __user *buffer,
+				       size_t count, loff_t *ppos)
+{
+	struct sof_client_dev *cdev = file->private_data;
+	struct sof_msg_inject_priv *priv = cdev->data;
+	struct sof_ipc_reply *rhdr = priv->rx_buffer;
+
+	if (!rhdr->hdr.size || !count || *ppos)
+		return 0;
+
+	if (count > rhdr->hdr.size)
+		count = rhdr->hdr.size;
+
+	if (copy_to_user(buffer, priv->rx_buffer, count))
+		return -EFAULT;
+
+	*ppos += count;
+	return count;
+}
+
+static ssize_t sof_msg_inject_dfs_write(struct file *file, const char __user *buffer,
+					size_t count, loff_t *ppos)
+{
+	struct sof_client_dev *cdev = file->private_data;
+	struct sof_msg_inject_priv *priv = cdev->data;
+	struct device *dev = &cdev->auxdev.dev;
+	int ret, err;
+	size_t size;
+
+	if (*ppos)
+		return 0;
+
+	size = simple_write_to_buffer(priv->tx_buffer, SOF_IPC_MSG_MAX_SIZE,
+				      ppos, buffer, count);
+	if (size != count)
+		return size > 0 ? -EFAULT : size;
+
+	ret = pm_runtime_get_sync(dev);
+	if (ret < 0 && ret != -EACCES) {
+		dev_err_ratelimited(dev, "debugfs write failed to resume %d\n", ret);
+		pm_runtime_put_noidle(dev);
+		return ret;
+	}
+
+	/* send the message */
+	memset(priv->rx_buffer, 0, SOF_IPC_MSG_MAX_SIZE);
+	ret = sof_client_ipc_tx_message(cdev, priv->tx_buffer, priv->rx_buffer,
+					SOF_IPC_MSG_MAX_SIZE);
+	pm_runtime_mark_last_busy(dev);
+	err = pm_runtime_put_autosuspend(dev);
+	if (err < 0)
+		dev_err_ratelimited(dev, "debugfs write failed to idle %d\n", err);
+
+	/* return size if test is successful */
+	if (ret >= 0)
+		ret = size;
+
+	return ret;
+};
+
+static int sof_msg_inject_dfs_release(struct inode *inode, struct file *file)
+{
+	debugfs_file_put(file->f_path.dentry);
+
+	return 0;
+}
+
+static const struct file_operations sof_msg_inject_fops = {
+	.open = sof_msg_inject_dfs_open,
+	.read = sof_msg_inject_dfs_read,
+	.write = sof_msg_inject_dfs_write,
+	.llseek = default_llseek,
+	.release = sof_msg_inject_dfs_release,
+
+	.owner = THIS_MODULE,
+};
+
+static int sof_msg_inject_probe(struct auxiliary_device *auxdev,
+				const struct auxiliary_device_id *id)
+{
+	struct sof_client_dev *cdev = auxiliary_dev_to_sof_client_dev(auxdev);
+	struct dentry *debugfs_root = sof_client_get_debugfs_root(cdev);
+	struct device *dev = &auxdev->dev;
+	struct sof_msg_inject_priv *priv;
+
+	/* allocate memory for client data */
+	priv = devm_kzalloc(&auxdev->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->tx_buffer = devm_kmalloc(dev, SOF_IPC_MSG_MAX_SIZE, GFP_KERNEL);
+	priv->rx_buffer = devm_kmalloc(dev, SOF_IPC_MSG_MAX_SIZE, GFP_KERNEL);
+	if (!priv->tx_buffer || !priv->rx_buffer)
+		return -ENOMEM;
+
+	cdev->data = priv;
+
+	priv->dfs_file = debugfs_create_file("ipc_msg_inject", 0644, debugfs_root,
+					     cdev, &sof_msg_inject_fops);
+
+	/* enable runtime PM */
+	pm_runtime_set_autosuspend_delay(dev, SOF_IPC_CLIENT_SUSPEND_DELAY_MS);
+	pm_runtime_use_autosuspend(dev);
+	pm_runtime_enable(dev);
+	pm_runtime_mark_last_busy(dev);
+	pm_runtime_idle(dev);
+
+	return 0;
+}
+
+static void sof_msg_inject_remove(struct auxiliary_device *auxdev)
+{
+	struct sof_client_dev *cdev = auxiliary_dev_to_sof_client_dev(auxdev);
+	struct sof_msg_inject_priv *priv = cdev->data;
+
+	pm_runtime_disable(&auxdev->dev);
+
+	debugfs_remove(priv->dfs_file);
+}
+
+static const struct auxiliary_device_id sof_msg_inject_client_id_table[] = {
+	{ .name = "snd_sof.msg_injector" },
+	{},
+};
+MODULE_DEVICE_TABLE(auxiliary, sof_msg_inject_client_id_table);
+
+/*
+ * No need for driver pm_ops as the generic pm callbacks in the auxiliary bus
+ * type are enough to ensure that the parent SOF device resumes to bring the DSP
+ * back to D0.
+ * Driver name will be set based on KBUILD_MODNAME.
+ */
+static struct auxiliary_driver sof_msg_inject_client_drv = {
+	.probe = sof_msg_inject_probe,
+	.remove = sof_msg_inject_remove,
+
+	.id_table = sof_msg_inject_client_id_table,
+};
+
+module_auxiliary_driver(sof_msg_inject_client_drv);
+
+MODULE_DESCRIPTION("SOF IPC Message Injector Client Driver");
+MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(SND_SOC_SOF_CLIENT);